Gauge



July 1 1924.

H. BACHARACH GAUGE 5 Sheets-Sheet 1 Filed March 14 1921 INVEIVOR WWWJuly 1 1924. 1,499,759

1 I H.BACHARACH GAUGE Filed March 14, 1921 5 Sheets-Sheet 2 flB 7F'IEESQ;

if-W W 4/ July 1 1924.

- H. BACHARACH GAUGE Filed March 14 1921 5 Shets-Sheet.

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v IN YEA/TOR H.BACHARACH July 1 GAUGE Filed March 14. 1921 5Sheets-Sheet 5 INVENTOI? .a wnw I 0,2;

6 @M? MW gnwe 5 nacnanacn, orrrr'rsnunen, rnniwsrnvnnm, assrenoa To 2na. INDUSTRIAL INSTRUMENT comrm, a coaronarron or 'rnmrsvnv a GAUGE.

Application filed March 14, 1921. "semi no. 452.2%.

To all whom it may concern:

Be it known that I, HERMAN BACHARAOH, a citizen of the United States,and a resident of Pittsburgh, in the county of Allegheny and State ofPennsylvania, have made a new and useful Invention in Gauges, of

which the following'is a specification.

The invention relates to'gauges. It has for its principal object theprovision of an improved gauge construction for giving a plurality ofranges for the indicating device, whether-such device be in the form ofa liquid in a transparent tube or in the form of a pointer or pencilmoved by a float or equivalent device under the influence of liquid towhich pressure is applied, to the end that a wide range of pressures maybe satisfactorily read by the use of a sin 1e" gauge, thus avoiding therequirement 0 a plurality of diifcrent' instruments to meet varyingconditions. The indicating device oftenest employed is an inclined glasstube in order to magnify the movement of the liquid, but other tubearrangements may be employed, as well aspressure operated pointers,pencil recorders and a wide range of other pressure operated devicesknown in the art. In order to indicate the $00 e of the invention aconsiderable number 0 different embodiments of the invention areillustrated, but it will be understood that these do not b any means comrehendthe possibilities o modification. e apparawe may be employed tomeasure either pressures or flows and to measure such pressures andflows both in gases and liquids.

Stated somewhat difierently. the improved gauges qr manometersaccomplish the function of obtaining with a. single device a practicallyunlimited number of measuring ranges. In their various forms certain ofwhich are illustrated and descri ed later) these devices mayindicate orrecord either simultaneously or alternately, by the use of speciallydesigned valves, or by the use of llquids of different specific gravity,a number of pressures o r volumes of the same or different range. I

Among the practical applications of the apparatus are the following: (1)to indi'- can; or record the draft in'a boiler furnace at variousplaces, as well as the forced or induced draft as furnished by a fan;(2;) to indicate or record the drafts and, air

pressures prevailing at various places in a regeneratin furnace, and thepressure and v0 ume of uel gas delivered to the furnace; and to indicateor record the flow of gases in a ventilating system.

Referring now to the drawings; a

Figure 1 illustrates in dia ammatic form one of the sim lest types olthe'invention Figs. 2, 3 an 4 similarl show in dia grammatic formseveral .m diments of the mventlon. Figs.- 5 and 6- illustrate a gau cwith .one form of valve 9. plied thereto in two different positions, anwith two difierent scales. F gs. 7, 8. and 9 are other views showing adifferent valve arrangement, and with the valve in three differentpositions, giving three ressure ranges. 14- indicate sti lanother valvearrangement. Figs. 15, 16 and 17 illustrate another construction withthe parts in three difierent positions of adjustment. And Figs. 18 to 20show another modification in which the invention is applied to measuringpressure.

Figs. 10 to in connection with afloat and recording mechanism.

It will be necessarylto go into detailed.

description only as to a limited number of the constructionsillustrated, the operation and construction of other forms based "uponthe same principle being readilyapparent Referring to Fig. 1, thenumeral 1 indicates the inclined gauge tube of glass or other suitabletransparent material along which may be arranged a plurality of suitab escales, two only of which scale a. above and 6 below) are illustra 2 and3 are tubes leading to different sources of pressure, the

upper end of the gauge tube 1 and the chambars or reservoirs 8 and 9,the two chambers being separated by the partition but in communicationbelow the lower edge oil such partition.

The chambers 8 and 9 are of difi'erent cross section. By way ofillustration, the areas may be in the relation of 9 to 1, and the crosssection of the gauge tube 1 is one fifth that of the chamber 9. Valves11, 12, 13, and 14: control the application of pressures from the pipes2 and 3.

The extent of movement of the liquid in the gauge tube 1 whendifferential pressure is applied to the upper end thereof and to thechambers with which the lower end of the tube is connected, will ofcourse be pro-. portional to the relative cross sectional areas of thegauge tube and chambers to which the pressures are applied. The greaterthe cross sectional area of the chambers as opposed to that of the gaugetube, the greater the movement in the gauge tube for each unit ofdificrence in pressure. When the difierences in pressure to be. measuredare low it will be desirable to get a maximum movement ,in the gaugetube per unit of difl'erential pressure, and the minus (or lower)pressure will be applied to the two chambers 8. and 9 in opposition tothe plus (or higher) pressure applied to the upper end of the gaugetube. This condition is secured in the construction of Fig. 1 by closinthe valves 11 and 12 and opening the va ves 13 and it. Under theseconditions the upper scale a is used.

@n the other hand, it the ditlerences in pressure to be measured are amaximum, the

' minus pressure will be applied only to the chamber 8 while the pluspressure is applied to the upper endof the gauge tube, this beingaccomplished by closing the valves 11, 12 and 13 and opening the valve14. At this time, the lower scale 6 will be used. lit will be understoodthat the illustrated unit divisions in scales or and i) are not at allrelatively accurate.

The following table indicates the difierent arrangements which may bemade for securing varying ranges of movement in the gauge tube, suchtable including the two examples already stated:

Leg 1 against legs 8 plus 9.

Leg 1 against leg 8. Leg l against leg 9. pd) Legs 1 plus 9 against leg8. 5) Legs 1 plus 8 against leg 9. lt is obvious that by the addition ofother chambers with suitable connections and valves, the ran e ofmovements of the liquid in the'gauge g ass might be widely am lified,but the foregoing is sudicient to ilustrate the principle involved.Where a lar e number of ranges are em loyed in a sing e j instrument thescales may e changed to suit the conditioner Fig. 2 illustrates aconstruction in which a plurality of ranges of movement in the gau eglass 15 are secured, such ranges being indicated by the scales 0, d, e.The tube 16 is adjustable vertically in the chamber 17, the lower of thedifferential pressures being applied to such tube 16 while the higherpressure is applied to the tube 18 at the upper end of the gauge tube.When the parts are in the position shown, the movement of the liquid inthe gauge tube is greatest and the scale 0 is employed. At this time thecross sectional area of the chamber 17, as opposed to that of the gaugetube governs the extent of movement of the liquid in the gauge tube. Itthe tube 16 is now moved down close to the liquid in the chamber 1? thescale 6 is brought into use, the first part of such scale correspondingto that of the scale 0 and the second part being composed of shorterunits. The cross sectional area of the chamber 17 governs the extent ofmovement of the liquid in the gauge tube, until the level of the liquidin the chamber 17 reaches the end of the tube 16, after which themovement of the liquid in the gauge tube for unit of change in pressureis reduced in proportion to the reduction of the sectional area of thetube 16 as compared with the chamber 17, so that that portion of thescale 6 having the shorter units comes into pla The t ird scale, d, hasits unit lengths the same as the shorter lengths of scale e, and suchscale is employed when the tube 16 is moved down to such an extent thatthe lower end thereof constantly extends below the surface of the liquidin chamber 17.

Fig. 3 illustrates a modification of the construction of F ig. 2 in thatthe tube 19 has two sections 20 and 21 of different cross sectionalarea. The ranges correspond to those of Fig. 2 with two additional ones.The first of these additional readings is'secured with the tube 19lowered so that the end of the section 20 is just above the level of theliquid, and the second when the tube is lowered still further so thatthe end of the section 20 is below the level of the liquid. The chamber22 and inclined gauge tube 23 correspond in construction to similarparts in Fig. 2 and suitable scales (not shown) will be employed as inthe other construction.

Fig. ll illustrates a modification in which two liquids 24 and 25 ofdifierent specific gravities, such as mercury and water are emplo ed,the liquid 24 being the mercury and 25 eing the water. The gauge glasses26 and 27 indicate the levels of the mercury and water respectively, fbeing the scale for the glass 26 and g the scale for the glass 27. Theopening 28 between the chambers 29 and 30 is closed by. the valve 31,when the level of the lower end of the tube 27, such closing movementbeing caused by the float 31. This stops the movement of the water 25and the higher pressures are then observed upon the lower gauge glass,26. The device is thus provided with measuring ranges for high and lowpressures, a very'heavy liquid being preferably employed for the highpressures and a very light one for the low pressures. Figs. 5 and 6illustrate an arrangement for giving two ranges, one for high and onefor low pressure, with asingle valve or three way cook 32 for shiftingfrom one range to the other. When the valve is in the POSltlOIL of Fig.5, the plus pressures are applied to chamber 33 and 34 and the minuspressure to chamber 35, thus giving the high pressure range in the glass36. The low pressure range is secured when the valve is shifted to theposition of Fig. 6 at which time the plus pressure-is applied to chamber33 and the minus pressure to chamber 34 and 35. The pipes 37 and 38 maybe provided with valves 39 and 40 linked together, as illustrated togive simultaneous opening for use when velocity readings are to betaken, such valves bein kept closed until, the valve 32 is ositioned. I

igs. 7, 8 and 9 illustrate an arrangement giving three ranges for low,medium and high pressures. The low pressure range is secured with thevalves 41 and 42 in the positions of Fig. 7, with the chamber 43connected to the plus ressure and the chamhere 44 and45 with t e minuspressure, the glass 46 being provided with a suitable scale. The adustment of Fig. 8 gives the medium range, the plus pressure beingapplied to the chambers 43 and 45 and the minus pressure to the chamber44. Fig. 9 shows the valves in position to give the high pressure range,the chambers 43 and 44 bemg supplied with the plus pressure and thechamber 45 with the minus pressure.

Figs substitution of a single valve 47 for the two valves of the Fig. 7construction, so arranged as to give five ranges. In the position ofFig. 10, the low pressure range is secured,

the plus pressure being applied to the chamber 48 and the minus pressureto the chambers 49 and 51, giving a reading on the glass 50. Fig. 11indicates the position of the valve 47 for the .next range, the pluspressure being applied to the chamber 48 and the minus pressure to thechamber 49. The next pressure range is secured with the valve in theposition of Fig. 12, at which time the plus pressure is connected tochambers 48 and 51 and the minus pressure to the chamber 49. Fig. 13indicates the valve position for the next range, the plus pressure beingapplied to the chamber 48 and the minus pressure to the chamber 51. Fig.14shows the valve in position for use with the high- 10, 11, 12, 1'3 and14 illustrate the est pressure range, the plus pressure being applied tochambers 48 and 49 and the minus pressure to the chamber 51. Thisconstitutes one of the simplest and most practical application of theinvention.

Figs. 15, 16 and 17 illustrate a structure constituting a combination ofthe features-of Figs. 2, 3 and 4 and involves an application of all theprinciples of all the structures heretofore illustrated and described.In this structure, the two liquids of the Fig. 4 construction are.employed in conjunction with the float operated valve; also a verticallyadjusted member 52 constituting a modification of those shown in Figs. 2and 3.

In this device, two inclined gauge glasses 53 and 54 are employed foruse respectively with water or oil and mercury lying in layers the valve59. The member 52 comprises two sections 60 and 61 and may be adjustedto occupy any one of the three diiferent positions illustrated in Figs.15, 16 and 17.

Referring to Fig. 15, the lower pressure range is secured by closing thevalves 62 and 63. and applying the plus pressure to the tube 53 and theminus pressure to chambers 56 and 57, the valve 59 being open at thistime as illustrated. The movement of the liquid in the glass 53 is nowrelatively great per unit change in differential pressure, and ismeasured by a suitable. scale (not shown) along the glass. cury hasreached the bottom of the glass 53, the float closes the valve 59 andthe measurement is shifted to the glass 54 carrying the Before the levelof the mermercury. At this stage the plu pressure applied to the upperend of the glass 54 is opposed to the minus pressure in the chamber 57.The movement per unit change in pressure is relatively low so that thisadjustment or condition of the apparatus is suitable for measuringrelatively high pressures.

A difi'erent adjustment of the ranges may be'made with the parts stillin the position of Fig. 15 by opening the valve 62 so that the pluspressure is applied to the tube 53 and section 60, the minus pressurebeing applied as before to the chambers 56 and 57. This gives anadjustment for measuring'somewhat higher pressure ranges than theprevious adjustment, since the liquid displaced by the plus pressure inthe section 60 reduces the volume of the liquid withdrawn for the tube53 by the upward movement of the level in the chamber 56. After thevalve 59 is closed the measurement of the level of the mercury in thetube 54 occurs, the section of such tube being in opposition to thesection of the chamber 57 to Fig. 16 with the valves adjusted as in thepreceding position, that is, with the plus pressure applied to the upperend of the gauge glass 53 and to the section 61 and with the minuspressure applied to the chambers 56 and '7. This gives a still highermeasuring range than the preceding position since the amount of liquidin the section 61 displaced by the plus pressure is reater than thatdisplaced in the section 1n the preceding operation and the withdraWalfrom the tube 53 to raise the level in the chamber 56 correspondinglyless. After the level in 56 has risen so as to close the valve 59, themeasurement by the mercury, in the tube 54 is the same asheretoforedescribed.

fourth range for still higher pressures is secured by adjustingthemember 52 to the position of Fig. 17, at which time the entire areaof the chamber or section 55 is exposed to the .plus pressures, theraising and lowering of the level in such section and the tube 53 perunit of difi'erential pressure is reduced to a minimum. The operationafter the closing of the valve 59 and the shift to a 1 measurement bythe heavier liquid in the glass 5-4 follows the operation heretoforedescribed, the movement of the heavier liquid in its glass being reducedto a minimum under these conditions with the plus pressure applied. tothe section 55.

Another measuring range may also be socured with parts in the positionof Fig. 17, but with the motion 61 open to the atmosphere and with pluspressure applied to the upper end ofthe gauge glass 53 and minuspressure applied to the chambers 56 and 57.

A number of other combinations of the chambers might also be made ifdesired to secure still other ranges, but the foregoing is sufieient toillustrate thepossibilities involved.

Fig. 18 indicates an application of the invention to a case in which, afloat device with suitable recordingmeans takes the place of theindicating gauge glasses of the preceding embodiments of the inventionthe device being adapted to measure either pressures (compared withatmospheric) as opposed to the flow meter devices heretofore illustratedor to measure difierential pres sures when it is desired to use thedevice as a flow meter. In this construction, 64: is the float casingcontaining the liquid in which is mounted the float 65 guided upon thehollow rod 66. The float is provided with the usual pencil .arm 67extending upward to a position adjacent the recording drum 68. p Thecasing 64 is divided by the partition 69 into two chambers 70 and 71 andthe float is also divided into two chambers 72 and 73 of difierent crosssectional areas. Three pressure lines 74, 75 and 76 leading respectivelyto the chambers 70, 73

neeavee and 72 areprovided, the chamber 71. above the float beingconnected with the negative or minus pressure through the ho low guiderod 66, when the device is used as a flow meter, said rod being open atits upper end.

The supply of fluid to the chambers 70, 71, 72 and 73 may be controlledby a valve 77 whose arrangement of parts and difl'erent positions areillustrated diagrammatically in Figs. 19 to 22. Plus pressure is appliedto the valve through the passage '78, when the device is used as a flowmeter in measuring differential pressures. -W'hen the device is used asa pressure meter and the pressure in opposition to the plus pressure isatmospheric, the connection 79 does not come into play and suitablecommunication between the chamber 71 and the atmosphere is provided.This may be conveniently accomplished by removing the gasket 80 at theupper end of the casing 6.4;. The valve 77 is arranged to give fourmeasuring ranges dependent upon its position, either when the chamber 71is supplied with the minus pressure from the pipe 79 or when it isconnected with the atmosphere. The valve is cored out as indicated at 81in Figs. 19 to 22. The positions and ranges are as follows. I

First, with the valve as shown in ig. 19, the plus pressure from thepipe 78 is supplied to both the chambers 72 and 73 of the float throughthe pipes 75 and 76, thus giving a maximum movement of the float perunit of pressure. 'Second,'the valve is moved clockwise to the positionof Fig. 20 whichgives connection from the supply pipe 78 to the pipe 75only, so that the plus pressure is applied to the chamber 73 only. Themovement of the float per unit change of pressure is now less than withthe valve in its preceding position.

Third, the valve is moved further clockwise to the position of Fig. 21,at which time the supply pipe 7 8 is connected by the pipe 76 to thechamber 72 only, and since the cross sectional area of this chamberis'somewhat less than that ol the chamber 73, the movement of thefioatper unit change of pressure is less than that secured when the valve isin the position of Fig. 20.

Fourth, the valve is moved still further in the clockwis direction tothe position of Fig. 22, which gives a minimum movement of the float perunit change of pressure. When the valve is in this position the supplypipe 78 is connected to the pipe 74: lead ing to the phamber 70, and themovement of the float is secured by reason of the variations in thelevel of the liquid in the easing induced by the varying pressureapplied to the relatively limited area of the surface of the liquidlying in the chamber 70.

What I claim is: v

1. In combination in a gauge for measuring fluid pressure, a fluidpressure-responsive means, means to receive the same including aplurality of pressure legs of different cross sectional area bearing adefinite relation to each other and having communlcation with the fluidof said means, connections for applying one of two fluid pressures,whose difference is to be measured, to a certain group of said legs,means whereby the application of such fluid pressures may be shifted soas to apply to certain legs of said rou selectively, thus varying therange 0 sai responsive means per unit of pressure, and connections forapplying the other of the two said pressures to said responsive meansthrough another of said legs outside of said group.

2. In combination in a gauge for measuring fluid premures, a liquidindicating.

means, a gauge glass therefor, a chamber for the liquid communicatingwith the glass,

" an adjustabl'etubular-member having a plu ing pressure through saidmember, and

rality of sections of different cross sectional area and openingdownwardly into the liquid in said chamber, connectionsfor applymeanswhereby the member maybe adjusted up and down to vary the range of said1ndicating means in said glass per unit of a pressure.

3. In combination in a gauge for measuring fluid pressures, liquidindicating means, a transparent tube carrying said liquid indlcatingmeans, a chamber containing a liquid in communication with the liquid ofsaid indicating means, a pressure leg of cross section different fromthat of said chamber extend-v ing through the top of the chamber and adjustable vertically therein so that its lower end may be either abovethe surface of the liquid of the chamber or below thesurface thereof,and means for applying fluid pressure through said pressure leg.

4. In combination in a gauge for measuring fluid pressures, an inclinedgauge glass a plurality of pressure legs or chambers'o diflerent crosssectional (area bearing a definite relation to each other and containinga liquid having communication with the lower end of the gauge glass,means for applying one of two fluid pressures whose difference is to bemeasured to said legs, means whereby the application of such fluldpressure may be shifted so as to apply to such legs selectively thusvarying the range of movement of the liquid in th gauge per unit ofpressure,vand connections for applying the other of two said pressuresto the upper end, of the gauge glass.

'5. In combination in a gaugefor measuring fluid pressures, an inclinedgauge glass, a plurality of pressure legs or chambers of diflerent crosssectional area bearing a dehto be measured-to the upper en ing fluidpressures, a flui nite relation to each other and containing a liquidhavin communication with the lower end of t e gauge glass, means forapplying fluid pressure to be measured to said le and means whereby theapplication of such fluid pressure may be shiftedso as to apply to such.legs individually or gauge glass, cans for applying-the lower of saidpressures to one of sai. legs, and means whereby such fluid pressure maybe shifted from one leg to another thus vary- .ing. the range ofmovement of the liquid in the gauge per unit of differential pressure.

7; In combination in a gauge for measuring fluid pressures, an inc inedgauge glass, a lurality of pressure legs or chambers of diEere-nt crosssectional area having a definite relation to each otherand containing aliquid havin communication with the lower end oft e gauge glass, meansfor applying the higher of two differential pressures to be measured tothe upper end of the gauge glass, means for applying the lower of saidpressures to one of said legs, and means whereby such fluid pressure maybe shifted from one Is to another or to various combinations 0 I thelegs thus varying the range of movement of the liquid in the gauge per.unitof differential pressure.

8. In combination in a auge for measurpressure-responsive means, meansto receive the same including legs of difierent cross sectional areahaving communication with the fluid of said of the means, a connectionfor applying one of two fluid pressures, whose diflerence is to .bemeasured, to one leg so as to tend to move thexresponsive means in onedirection, other communicating means for ap lying the other of saidfluid pressures to the other legs so as to tend to move the responsivemeans in liquid lying upon the heavier liquid with its surface shove thelevel of the lower end of the upper glass, endmeens for epplyingdifterentinl pressures to be measured to the upper ends of the twoglasses end to seid pressure is or chamber.

10. n combinution in o gauge for mensuring fluid pressures, e pair ofgouge glesses, a, pressure leg or chumber communicating with the lowerend of both glasses at difierent levels respectively,btwo liquids in thechamber of ditlerent density with that of greater densit having itslevel between the lower ends 0 the glesses, end the lighter liquid lyingupon the heavier liquid with its 'surztece shove the level of the lowerend oil the upper gloss, menus for upplying difierentiul pressures to bemeasured to the upper ends or the two glasses end to seid pressure legor chember, end menus whereby the u word movement of the lighter liquidmuy e checked utter such movement hes progressed e predetermineddistance, end theruessuring action shifted to the movement of theheavier liquid in its gouge gloss.

ll. lln combination in e gauge for mensuring tluid pressures, e peir ofgouge glasses, e peir of pressure legs or chumbers, one or whichcommunicetes with the lower end of both glumes ct different levelsrespectively, two liquids in the chembers oi ditlerentdem sity with thatof wreeter density hoving its level between toe lower ends of theglosses, end the lighter liquid lying upon the heevier liquid with itssurface shove the level of the lower end the upper gless, n

communicnticn between the two cheroloers below level of the denserliquid, menus for upplying ditlerentiel pressures to the up per ends ofthe two glasses and to the two chambers or legs shove the surface or theliquids therein, end meens whereby the upwerd' movement of the lighterliquid is checked alter such movement has progressed e predetermineddistance thus shifting the meesuring ection the movement oi the heevierliquid in its 112. In combinstion in e for mensneonate uring fluidpressures, u peirof pressure legs or chambers, one of which communicateswith the lower end of both glasses st difierent levels respectively, twoliquids in the chambers of diderent density with that of router densityhaving its level between the ower ends of the glasses, and the lighterliquid lying upon the heavier liquid with the surface above the level ofthe lowerend of the upper glass, it communication between the twochambers below the level of the denser liquid, means for applyingdiflerentiul pressures to the upper ends of the two glasses and to thetwo chambers or legs above the surface of the liquids therein, e, vulvefor cutting 0d the pressure connection to the chamber contuining the twoliquids, and eutometic menus tor closing such vulve after the upwardmovement of the liquid in the chamber has progressed u predetermineddistance.

13. In combination in u gouge for mensuring fluid pressures, e peir ofgouge glasses, e poor of pressure legs or chambers, one of whichcommunicetes with the lower end of both losses et dilderent levelsrespectively, two liquids in the chambers of difierent density with thatof greater density having its level between the lower ends oi theglasses, end the lighter liquid lying upon the heavier li uid with itssurle/cesebove the lighter liquid in solid chumber end connected to thevalve end edepted to close such valve utter the liquid in hos movedupward at predetermined distance.

In testimony whereof, l hove hereunto subscribed my neme this lilth dnyoi March,

BACHARACH.

